Appabatus fob drying salt



UNITED sTATEs PATENT OEEioE. u

GEORGE C. ROBINSON, OF BOSTON, MASSACHUSETTS.

APPARATUS FOB DRYING- SALT.

Speccation of Letters Patent No. 31,827, dated March 26, 1861.

To all whom it may concern:

Be it known that I, GEORGE O. ROBINSON, of Boston, county of Suffolk, and State of Massachusetts, salt manufacturer, have invented a new land useful Machine for Drying Salt Preparatory to Grinding; and I do hereby declare that the following description, with the accompanying drawings, forms a full, clear, and exact specification thereof.

Heretofore the drying of salt, preparatory to grinding has been performed by means of one, two or more res, kindled, and kept burning underneath a long, flat stationary metallic trough, or platen, as it is technically termed. The salt to be dried is placed on one end of the platen, and is carried over the fires to its point of discharge at the other end of the platen by means of a number of knife-edged Scrapers-which are carried along in their course by any convenient application of mechanical power. The practical diiliculty and imperfection of this method, is the great liability of the salt to become burned or scorched in passing over the firesfor as it will be observed that the fires really act on only a small portion of the platen,-there is a constant telnptation to keep the lires up to as great an intensity as possible in order to get a fair amount of work out of the machine, and thereby the points immediately over the fires become very hot, and the Occasional scorching of the salt is almost inevitable. To remedy these difliculties I have invented my rotary salt drying machine, which is shown by the accompanying drawings, which form apart of this description.

Figure 1 is a horizontal view on line A. B. taken above the platen.Fig. 2 is a vertical section on line C. D. and Fig. 3 is a horizontal section on line E, F, through the fire chamber and furnaces, underneath the platen.

Similar letters represent similar parts in all the views. Y

(a) represents the circular platen which has a rotary motion in direction indicated by the red arrows The platen is fixed upon the upright shaft (c) which receives its rotary motion from the pulley (al) and the driving belt (e) or by any other convenient application of mechanical power.

The upright shaft (c) 'has a bearing on the bottom (f) which is reached y for oiling through the man-hole passage (g).

The salt is delivered from the hopper (it) by means of the spout at a point nearthence, by means'of the pin at (0) the entire section of Scrapers is set-at any desired angle so as to diffuse the salt more or less rapidly toward the periphery of the platen, Where it is finally thrown off by the discharging scraper (p) at a point of discharge (g), all of which clearly appears in Fig. l.

The action of the radiating teeth or scrapers (j) is such, as to leave the salt on the platen, in a series of very small ridges or windrows, to remedy which, I sometimes apply the supplementary scraper or leveler (1*), the bottom edge of which is left up a little space from the plateinanclthe action of which, is t0 level down the ridges or windrows, so as to spread the salt evenly upon the surface of theplaten.

To prevent the smoke and heat of the furnaces from escaping around the revolving platen I make a circular flange (s) near the periphery of the platen, which revolves in a packing of sand or other inconibustible powder (t) placed in a circular channel in the upper part of the outside casing of the heat chamber, as shown in Fig.,2.

I commonly use two furnaces (a) as shown in Fig. 3, and the smoke is finally discharged from the chimney flue at Having thus described my machine for drying salt-what I claim as my improvements therein and desire to secure by Letters Patent arel. The revolving platen, in combination with the teeth or Scrapers (j) or their equivalents, constructed and arranged substantially as described.

2. The discharging scraper (p) for the sand, or other incombustible powder, subpurposes set forth. stantially as described and for the purposes 3. The Supplementary scraper, or leveler set forth. (1') arranged in my machine substantially GEO. O. ROBINSON.

5 as described. Witnesses:

4;. Packing the outer periphery of the re- R. L. SPOFFORD, J r., Volvng platen of my rotary salt drier With LUTHER BRIGGS, J r. 

